Boiler



G. OSPELT Feb. 22, 1966 BOILER 3 Sheets-Sheet 2 Filed May 9, 1965 G.OSPELT Feb. 22, 1966 BOILER 5 Sheets-Sheet 5 Filed May 9, 1965 fn venfor:

Gas/av 0s? e/f- United States Patent O 3,236,212 BOILER Gustav Ospelt,70 Herrengasse, Vaduz, Liechtenstein Filed May 9, 1963, Ser. No. 279,266Claims priority, application Germany, May 12, 1962, O 8,743; Dec. 5,1962, 9,111 3 Claims. (Cl. 122-136) T-he present invention relationrelates to a boiler which comprises a substantially horizontallyarranged first water jacket having a substantially cylindrical outerwall and forming a combustion chamber for a )burner for liquid andgaseous fuels, and which also comprises a substantially horizontallyarranged second water jacket suriounding said first water jacket inspaced relationship thereto and having a substantially cylindrical innerwall, the interior of said second water jacket communicating with theinterior of said first water jacket.

Boilers of the above-mentioned type are known in which the outer wall ofthe first water jacket is coaxially arranged With regard to the innerwall of the second water jacket. In the annular chamber between the twowater jackets .there is inserted a helical guiding wall so that thecombustion gases passing from the combustion chamber at the front endthereof into the said annular chamber pass through the latter along ahelical path in the longitudinal direction of said annular chamber. Thespeed of the gases cooling off can be held constant by so arranging thepitch of the helical guiding wall windings that it will decrease in thedirection of the offJfiowing gases.

It is an object of this invention, with a boiler of the above-mentionedtype, by simple structural arrangements and means and, above all,without additional inserts, to bring about that the speed of thecombustion gases cooling off will remain -approximately constant over atleast the major portion of their path through the boiler, becauseotherwise with a decrease in the gas velocity due to the decrease intemperature, also a reduction in the heat transfer occurs.

It is another object of this invention to provide a boiler with twowater jackets arranged noncoaxially with and in spaced relationship toeach other, in which the gases passing through the annular chamlberbetween said jackets will be subjected to strong turbulence and willintensively sweep the walls of the water jackets.

These and other objects and advantages of the invention will appear moreclearly from the following specification in connection with theaccompanying drawings, in which:

FIGURE l is a vertical central section through a boiler;

FIGURE 2 is a vertical section along the line II-II of FIGURE l;

FIGURE 3 is a vertical central section through a boiler of anothermodification;

FIGURE 4 is a vertical section taken along the line IV-IV of FIGURE 3;

FIGURE 5 shows a vertical central section through a modified boileraccording to the invention;

FIGURE 6 is a section through still another modification of a boiler ofthe invention.

The present invention is characterized primarily in that the first waterjacket is arranged eccentrically with regard to the inner wall of thesecond water jacket, said first water jacket being provided with adischarge opening extending in the direction of the generatrix ofcylinder. This discharge opening establishes communication of thecombustion chamber with the annular chamber between the first and secondwater jackets, at least near that portion of said annular chamber whichhas the 3,236,212 Patented Feb. 22, 1966 ICC maximum clear width.Furthermore, in conformity with this invention, the flue gas dischargefrom said annular chamber is spaced from said discharge opening incircumferential direction by a distance greater than that between saiddischarge opening and that portion of said annular chamber which has theleast clear width, the water jackets communicating with each other forconveying water.

This arrangement brings about in a particularly simple manner that thecross-section of the annular chamber which is located between the twowater jackets and is passed through by the gases, continuously decreasesin fiow direction, while the gases pass through said annular chamber intangential direction, i.e. in circumferential direction. Theeccentricity between said two water jackets may be so dimensioned thatthe reduction in the cross-section is of such magnitude that the gasvelocity will at least approximately remain constant. This brings aboutas uniform as possible a heat transfer over the length of the path ofthe gas within said annular chamber. Expediently, the discharge openingin the first water jacket extends over about the axial length of thisfirst water jacket so that the annular chamber will, from the very startbe well passed through throughout by the gases. The inner wall of thesecond water jacket may, at the place of the flue gas withdrawal beprovided with a channel-like depression in axial direction toward theliue gas discharge.

Referring now to the drawing in detail, the boiler according to FIGS. land 2 comprises a first water jacket 1 with cylindrical horizontallyarranged walls 2 and 3. The second water jacket 4 is formed by avertically arranged cylindrical outer wall 26 and a horizontallyarranged cylindrical inner wall 5. The two water jackets 1 and 4 areconnected at their back sides for conveying water (FIG. l). The feedingline and the return line of the boiler are designated with the referencenumerals 10 and 11, respectively. The inner chamber 8 of the rst waterjacket 1 and the annular chamber 13 are at the front side of the boilerclosed by a detachable cover 19 carrying the burner 9. The first waterjacket 1 is eccentrically located with regard to the inner wall 5 of thesecond water jacket, i.e. is somewhat offset toward the left with-regard to FIG. 2. The cross-sectionally widest portion of the annularchamber 13 is according to FIG. 2 located on the right-hand side. Near aportion above said widest portion the water jacket 1 is provided with adischarge opening 12. This discharge opening 12 is offset byapproximately 45 with regard to the cross-sectionally widest portion ofthe annular chamber 13. The flue gas discharge 14 is located at thehighest portion of annular chamber 13 (with regard to the drawing), i.e.is arranged offset by approximately with regard to the crosssectionallywidest or cross-sectionally narrowest portion of' the annular chamber13. Annular chamber 13 is connected with the flue gas discharge 14 by atrough or passage-like axially extending depression 15 in the inner wall5 which at one side thereof is provided with a sheet metal member 18.The lower edge of member 18 is spaced from wall 2 by a forwardlyincreasing distance (FIG. 2) and brings about that the gases, prior toreaching the trough or passage-like depression 15, will everywhereuniformly pass through the annular chamber 13. Between the depression 15and the discharge opening 12, the annular chamber is closed by apartition 27 arranged in annular chamber 13 and extending over the axiallength thereof. Therefore, the gases can pass only along the pathindicated by the arrow 28 in circumferential direction aboutappreximately the entire circumference of the rst water jacket 1. Whiledoing so they first pass at approximately constant speed through thecross-sectionally narrowing portion of the annular chamber 13 and thenpass through the cross-sectionally broadening portion in which theirvelocity will be reduced. In view of the decrease in velocity in thisshorter portion of the circumference of the annular chamber, the heattransfer will be somewhat decreased. However, due to the reduction invthe gas velocity, the deviating resistance during the devia- Ation ofthe gases from the circumferential direction into the axial direction,will be greatly reduced. In the upper portion of the water chambersurrounded by the wall 26, there is arranged the heater 29 for theconsumer water. This heater has a T-shaped pipe 30 which is passedthrough by boiler water and serves as heat exchanger and communicateswith the second water jacket 4. Into the vertical portion of theT-shaped pipe 30 extends a conduit 25 which communicates with the firstwater jacket 1. The feeding line and the discharge line of the heaterfor v the consumer water are designated with the reference numerals 22and 23, respectively.

The boiler according to the invention may, in an advantageous manner beso designed that it is provided with three water jackets arrangedeccentrically with regard to each other so that between the first andthe second water jacket there will be formed an inner annular chamber,while between the second and third water jacket there will be formed anouter annular chamber. Furthermore, the combustion chamber, the twoannular chambers, and the flue gas discharge are so connected to eachother that the two annular chambers will be passed through successivelyby the combustion gases in one and the same circumferential direction.Such a boiler, which yields a particularly high exploitation of the heatof the combustion gases, is illustrated in FIGS. 3 to 6. Morespecifically, the boiler according to FIGS. 3 and 4 has a first waterjacket 101 confining a combustion chamber 102 and formed by twocylindrical horizontally arranged walls 103 and 104. Wall 103 has itsrear end provided with a bottom 105 which closes the combustion chamber102. Mounted on said bottom 105 is a fire-resistant lining 106. Firstwater jacket 101 is surrounded in spaced relationship thereto by asecond water jacket 107 which is composed of two cylindricalhorizontally arranged walls 108 and 109. Between the water jackets 101and 107 there is provided an annular inner chamber 110. The second waterjacket 107 is surrounded in spaced relationship thereto by a third waterjacket 111 which is composed of two cylindrical horizontally arrangedwalls 112 and 113. Between the water jackets 107 and 111 there isprovided an annular outer chamber 114. The rear end of wall 113 isequipped with a bottom 115. The water jackets 101, 107 and 111 areclosed at their front end, whereas their rear ends are open andcommunicate with each other in a water-conducting manner. For purposesof obtaining a good water circulation, the bottom portions of the waterjackets are interconnected by connections 116 and 117. Furthermore,

the first water jacket 101 and the second water jacket 107 have theirupper portion connected to a connection 118, while the second waterjacket 107 communicates with the third water jacket 111 by a connection119.

The highest portion of the third water jacket 111 is by means of astand-pipe 120 and at a somewhat lower section by means of two returnpipes 121 connected with a heater for consumer water (not illustrated)which heater is heated up by boiler water. In view of the thermosyphoneffect, the boiler water circulates through the heater for the consumerwater. The connection 119 is below the stand-pipe 120 arranged in such away that the boiler water heated in the second water jacket 107 can flowdirectly into the stand-pipe 120. Mounted on the first water jacket 101is a stand-pipe 122 which extends in spaced relationship through theconnection 119 and also throughthe stand-pipe 120 and extends into theheater for the consumer water. The hottest boiler water passes .throughstand-pipe 122 from water jacket 101 upwardly whereby the thermo-.syphoncirculation through the heater for the CQIJSUIDGI Water will be greatlyaccelerated.

The annular chambers and 114 are at the front end closed by a cover 123which carries a burner 124. The boiler feeding line is designated withthe reference numeral 125 while the boiler return line is designatedwith the reference numeral 126.

The first water jacket 101 is arranged eccentrically with regard to thesecond water jacket 107 and more specifically, according to FIG. 4, isoffset toward the left in downward direction. On the right-hand side,the first water jacket 101 has a discharge opening 127 which extends inthe direction of a generatrix of cylinder. The gases pass fromcombustion chamber 102 through opening 127 into the inner annularchamber 110 which is passed through by the gases in circumferentialdirection. During this course the gases first pass through the longnarrowing portion of the annular chamber 110 and then through a shortbut again broadening portion. The gases then pass into the outer annularchamber 114 through an overflow opening 128 in the second water jacket107 which over'- ow opening extends along a generatrix of this waterjacket 107 and is offset by approximately 315 with regard to thedischarge opening 127. Between the discharge opening 127 and theoverflow opening 128 there is in the annular chamber 110 provided apartition 129. The

' again broadening portion of the inner annular chamber 110 brings aboutthat the gas velocity decreases and thus the deviating resistancesdecrease during the deviation of the gases at the overflow opening 128.The second water jacket 107 is eccentrically arranged with regard to thethird water jacket 111 and in conformity with FIG. 4 is offset towardthe left. Also the outer annular chamber 114 is passed through by thegases in circumferential direction over a long cross-sectionallynarrowing portion and a short cross-sectionally widening portion. At theend of the widening portion of the outer annular chamber-114, saidchamber 114 is connected to the flue by means of a flue gas discharge130. Between the flue gas discharge and the overflow opening 128 thereis provided a partition 131 in the outer annular chamber 114.

FIGURE 5 illustrates an embodiment of the boiler in which with the samelocation of the discharge opening 127, and of the overflow opening 128and of the flue gas discharge 130, similar to FIG. 4, the eccentricitiesare so selected that annular chambers 110 and 114 will assume such ashape that at the end of their widening portion, i.e. at the overflowopening 128 and the flue gas discharge 130 they have a greater clearwidth than in the arrangement of FIG. 4. The first water jacket 101 iswith regard to the second water jacket 107 offset toward the left, whilethe second water jacket 107 is offset with regard to the third waterjacket 111 in upward direction. As a result thereof, particularly at theflue gas discharge 130, a sufficiently large clear cross-section of theouter annular chamber 114 is created the surface of which correspondssubstantially to the cross-sectional surface of the ue gas discharge130, so that, above all, at this location at which a considerabledeviation of the gasesis effected, the deviating resistances will beconsiderably reduced. Inasmuch as the temperature of the combustiongases, which in addition to the gas velocity also influences the heattransfer, has in the last portion of the outer annular chamber 114dropped already to a rather low value, the increase in the clearcross-section of the last-mentioned portion will not result in anymaterial drawback.

The heat transfer in this last-mentioned portion of the regard to eachother is selected in conformity with FIG.

4, whereas the eccentricity between the second and third water jacket isselected in conformity with FIG. 5. With this boiler, the narrowingportion of the inner annular chamber 110 is made as long as possible.The greatest width of the outer annular chamber 114 is, however, alsowith this boiler arranged where the strong deviation of the flue gasesfrom the tangential direction of flow into the axial direction of flowoccurs so lthat also at this location of deviation low deviatingresistances will be encountered. The widening of the outer annularchamber 114 at the flue gas discharge 130, which widening is created bythe eccentricity of the second and third water jackets in conformitywith FIGURES 5 and 6, has in particular with boilers of large axiallength and great through-flow quantities, the advantage that the centerangle of the ilue gas discharge 130 which has the shape of a ringsegment and should have a suiciently large cross-sectional surface, willnot have to exceed a desired permissible magnitude.

It is, of course, to be understood that the present invention is, by nomeans, limited to the particular constructions shown in the drawings,`but also comprises any modications within the scope of the appendedclaims.

What I claim is:

1. A boiler which includes: a substantially horizontally disposed rstwater jacket confining a combustion chamber for cooperation with aburner and having a substantially cylindrical outer wall, at least asecond substantially horizontal disposed water jacket surrounding saidfirst water jacket in spaced relationship thereto and communicating withsaid iirst water jacket while having a substantially cylindrical innerwall having its longitudinal axis offset with regard to the longitudinalaxis of the outer wall of said first water jacket so that the adjacentwalls of said two water jackets form with each other an annular charnberof crescent-shaped cross section, said first water jacket having anaxially extending discharge opening for the passage of `combustion gasesfrom said combustion charnber into said annular chamber, said dischargeopening being located at least near that portion of said annular chamberwhich has the greatest inside width, said annular chamber having outletmeans for the combustion gases which is oset circumferentially withregard to said discharge opening by an angle of between 270 and 360, andpartition means provided in said annular chamber and located betweensaid discharge opening and said outlet means.

2. A boiler which includes: a substantially horizontally disposed iirstwater jacket conniug a combustion chamber for cooperation with a burnerand having a substantially cylindrical outer Wall, a secondsubstantially horizontally disposed water jacket surrounding said rstwater jacket in spaced relationship thereto, said second water jacketcommunicating with said first water jacket and having a substantiallycylindrical inner wall having its longitudinal axis offset with regardto the longitudinal axis of the outer wall of said first water jacket sothat the adjacent walls of said two water jackets form with each other afirst annular chamber of crescent-shaped cross section, said first waterjacket having axially extending first discharge opening means for thepassage of combustion gases from said combustion chamber into said rstannular chamber, said rst discharge opening means being located at leastnear that portion of said rst annular chamber which has the greatestinside width, said first annular chamber having second discharge openingmeans offset circumferentially with regard to said rst discharge openingmeans by about 315, partition means in said first annular chamberbetween said first and second discharge opening means, a substantiallyhorizontally disposed third water jacket surrounding said second waterjacket and having a substantially cylindrical inner wall in spacedrelationship thereto, said third water jacket communicating with saidsecond water jacket and having a substantially cylindrical inner wallhaving its longitudinal axis offset with regard to the longitudinal axisof the outer wall of said second water jacket so as to confine therewitha second annular chamber of crescent-shaped cross section, said seconddischarge opening means forming a passage for the combustion gases fromsaid iirst annular chamber into said second annular chamber, said seconddischarge opening means being located at least near that portion of saidsecond annular chamber which has the maximum inside width, said secondannular chamber having an outlet for the gases which is offsetcircumferentially with regard to said second discharge opening means byabout 315 and partition means in said second annular chamber betweensaid second discharge opening means and said outlet.

3. A boiler according to claim 2, which includes gas deflector plates onthe water jacket walls inside said annular chambers.

References Cited by the Examiner UNITED STATES PATENTS 1,339 9/1839 DeWitt 122-134 3,007,457 11/ 1961 Ospelt 122-37 FOREIGN PATENTS 208,557 4/1960 Austria. 1,004,513 11/1951 France.

859,248 1/1961 Great Britain.

FREDERICK L. MATTESON, JR., Primary Examiner.

KENNETH W. SPRAGUE, PERCY L. PATRICK,

Examiners.

1. A BOILER WHICH INCLUDES: A SUBSTANTIALLY HORIZONTALLY DISPOSED FIRSTWATER JACKET CONFINING A COMBUSTION CHAMBER FOR COOPERATION WITH ABURNER AND HAVING A SUBSTANTIALLY CYLINDRICAL OUTER WALL, AT LEAST ASECOND SUBSTANTIALLY HORIZONTAL DISPOSED WATER JACKET SURROUNDING SAIDFIRST WATER JACKET IN SPACED RELATIONSHIP THERTO AND COMMUNICATING WITHSAID FIRST WATER JACKET WHILE HAVING A SUBSTANTIALLY CYLINDRICAL INNERWALL HAVING ITS LONGITUDINAL AXIS OFFSET WITH REGARD TO THE LONGITUDINALAXIS OF THE OUTER WALL OF SAID FIRST WATER JACKET SO THAT THE ADJACENTWALLS OF SAID TWO WATER JACKETS FORM WITH EACH OTHER AN ANNULAR CHAMBEROF CRESCENT-SHAPED CROSS SECTION, SAID FIRST WATER JACKET HAVING ANAXIALLY EXTENDING DISCHARGE OPENING FOR THE PASSAGE OF COMBUSTION GASESFROM SAID COMBUSTION CHAMBER INTO SAID ANNULAR CHAMBER, SAID DISCHARGEOPENING BEING LOCATED AT LEAST NEAR THAT PORTION OF SAID ANNULAR CHAMBERWHICH HAS THE GREATEST INSIDE WIDTH, SAID ANNULAR CHAMBER HAVING OUTLETMEANS FOR THE COMBUSTION GASES WHICH IS OFFSET CIRCUMFERENTIALLY WITHREGARD TO SAID DISCHARGE OPENING BY AN ANGLE OF BETWEEN 270 AND 360*,AND PARTITION MEANS PROVIDED IN SAID ANNULAR CHAMBER AND LOCATED BETWEENSAID DISCHARGE OPENING AND SAID OUTLET MEANS.